PingPang test

#include <cstdio>
#include <thread>
#include <condition_variable>
#include <mutex>
#include <chrono>

int main() {
    enum { COUNT = 1000000 };
    volatile int ping = 0, pang = 0;
    auto clock = std::chrono::high_resolution_clock::now();
    std::condition_variable cvPing, cvPang;
    std::mutex mtx;

    std::thread thd([&](){
        cvPing.notify_all();
        std::unique_lock<std::mutex> lock(mtx);
        while (pang < COUNT) {
            cvPang.wait(lock);
            ++pang;
            cvPing.notify_all();
        }
    });

    {
        std::unique_lock<std::mutex> lock(mtx);
        while (ping < COUNT) {
            cvPing.wait(lock);
            ++ping;
            cvPang.notify_all();
        }
    }

    thd.join();
    std::printf("PING: %d, PANG: %d, Time used: %lldms\n", ping, pang, (std::chrono::high_resolution_clock::now() - clock).count() / 1000000);
}